CN1049614C

CN1049614C - Apparatus for manufacturing automotive steering rack

Info

Publication number: CN1049614C
Application number: CN95121326A
Authority: CN
Inventors: 安田务; 源淳
Original assignee: Showa Corp
Current assignee: Showa Corp
Priority date: 1994-12-27
Filing date: 1995-12-18
Publication date: 2000-02-23
Anticipated expiration: 2015-12-18
Also published as: DE19544786C2; DE19544786A1; CN1131589A; JPH08174126A; US5722281A

Abstract

An automobile steering rack manufacturing apparatus has a material clamp for holding a hollow pipe-like rack material that has a solid core bar inserted therein. A forming roll on the apparatus has an outer periphery with rack teeth formed thereon, while a material drive causes a mutual rolling of the material clamp and the forming roll, thereby cutting rack teeth into the material. The clamp moves in the tangential direction of the forming roll orientation, and a tooth depth controller controls the distance between the rack material held in the material clamp, and the forming roll.

Description

Make the equipment of automobile steering rack

The present invention relates to a kind of equipment that forms the manufacturing automobile steering rack of rack tooth at the side surface of a hollow tube.

The common tooth bar that is used for automotive steering structure or similar means from a pole by flattening its a part of outer surface, forming rack tooth at flattening partially then and make.For preferable rack material, be in order to satisfy lightweight requirement with hollow pipe.

The Japan Patent of communique Sho58-31257/1983 (JP-B2) has illustrated a kind of method that forms rack tooth by plastic working one rack material.In this method, with one have with the patrix of the complementary profile of tooth of rack tooth at rack tooth shaped portion perpendicular to the direction extrded material of material axis.

The Japan Patent of communique Hei3-5892/1991 (JP-B2) illustrated a kind of by adopt one have with at the shaping mould of the identical tongue and groove of the rack tooth of flat part, then drift is press-fitted hollow pipe into and forms the method for a row tooth in the flat part of hollow tubular rack material.The part that material is flat is forced in the tongue and groove of shaping mould.

Yet two methods of prior art are included in the preproduction phase that the pipe with plane surface forms side rack tooth shaped portion.This unfavorable productivity ratio just occurred.In addition, the processing that is shaped needs higher thrust, also easily forms burr around new formation rack tooth.

An object of the present invention is to provide a kind of simplification rack tooth shaping racks processed manufacturing equipment.Another object of the present invention is to produce the less rack tooth that forms down with smaller power and at burr.

A kind of equipment provided by the invention comprises: one is used for fixing a rack material fixture that is inserted with the hollow tubular rack material of a plug in it; One is formed with the forming rolls of rack tooth shape at its outer surface; One causes the mutual telecontrol equipment that rack material fixture and forming rolls move mutually in the tangential direction in forming rolls orientation; And feed arrangement that is used for adjusting distance between the rack material of being fixed and the forming rolls by the rack material fixture.The rack material fixture comprises that one changes rack material and shaping rolled the angular adjustment apparatus of fixed angles.

The rack material fixture can also forming rolls radially opposite side fix two rack material Face to face, wherein, mutually telecontrol equipment causes that each rack material moves in relative direction.

Because forming rolls presses to each rack material, cause tangential direction the moving on forming rolls of rack material with the forming rolls direction, forming rolls is clamp-oned the tangential force that rack material causes and is rotated in the rack tooth shape of forming rolls.

The present invention has saved and has been shaped the first time that needs to form the rack tooth plane surface on rack material, and can directly form rack tooth at round tube, thereby, simplified processing, improved productivity ratio.

In addition, the feed arrangement of each pre-determined number circulation (such as circulation each time) by forming rolls and the mutual rolling of rack material can reduce the distance between forming rolls and the rack material axis.Therefore, itself increases progressively the wedging material forming rolls in the circulation of each pre-determined number, therefore need not with big power only need just can form rack tooth with smaller power in each feed.More advantageously, this means that rack tooth can not form burr, therefore, just can form the rack tooth with superior mechanical intensity.

One change rack material to the angular adjustment apparatus of forming rolls fixed angles promptly refer to rack material can with the rack material formation rack tooth that axially meets at right angles, perhaps also can easily axially form rack tooth at an angle with rack material.

By fixing two rack material, make it mutually Face to face at forming rolls opposite side radially, when two rack material are in the opposite direction mobile, the contact force that is applied to forming rolls by rack material is cancelled out each other along the each point that is symmetrical in the forming rolls axis, therefore, need not to increase the diameter of forming rolls so that guarantee the axial bending rigidity of forming rolls.As a result, can reduce the size of equipment.

Even the diameter of forming rolls reduces, forming rolls also is difficult to bending, therefore, increases forming pressure and does not sacrifice the machining accuracy that rack tooth is shaped and become possibility.

Owing to can reduce the diameter of forming rolls, contact area between forming rolls and the workpiece also can reduce, thereby, increased the extruding force of each unit are, therefore, increase the eating the depth degree of part in compression of the each rolling circulation of forming rolls and reduced process time.

In addition, because two tooth bars form simultaneously, working ability is to double.

By the accompanying drawing of detailed description given below and preferred embodiment of the present invention, will more fully understand the present invention, preferred embodiment is explanation as an example only, rather than is used for limiting the present invention.Among the figure:

Fig. 1 is the front view of tooth bar former one embodiment of the present invention;

Fig. 2 is the vertical view of Fig. 1;

Fig. 3 is the view that intercepts along the III-III line in Fig. 2;

Fig. 4 is the schematic diagram of rack material fixture;

Fig. 5 is the detailed maps of Fig. 4 major part;

Fig. 6 A is the profile that intercepts along the VI-VI line in Fig. 4;

Fig. 6 B is the detailed view of a part shown in Fig. 6 A;

Fig. 7 A and 7 is profiles of a plug;

Fig. 8 is the schematic diagram of rack material with respect to the forming rolls Working position; And

Fig. 9 is the schematic diagram with a steering rack of present device formation.

According to the present invention, tooth bar 10 as shown in Figure 9 is to obtain from one as the hollow circular-tube of rack material 11, and forms many across the axial rack tooth 12 of rack material 11 on the part outer peripheral face of material.

Fig. 1 to 6 illustrates a kind of equipment of making this tooth bar 10.As shown in the figure, equipment 20 comprises a lathe bed 21, a material clamping element (being the material fixture) 22, one plug adjusting device 23, a material drive unit (being mutual telecontrol equipment) 24 and one tooth depth adjuster (being feed arrangement) 25.Along with a plug 26 injects rack material 11, cause the mutual motion of rack material 11 and forming rolls 27 in the tangential direction of forming rolls 27, thereby, form rack tooths in rack material 11.Forming rolls 27 has the tooth bar of a tooth and tooth 12 complementations at its outer peripheral face.

Material clamping element 22 comprises that one changes the angle demodulator (being angle regulator) 28 of the fixed angle (being machining angle) of 11 pairs of forming rolls 27 of rack material.

To describe lathe bed 21, material clamping element 22, plug adjusting device 23, material drive unit 24, tooth depth adjuster 25 and angle demodulator 28 now in detail.

A. lathe bed 21 (Fig. 1 to 3)

Lathe bed 21 has left and right side plate 21A and 21B and upper and lower plate 21C and 21D.Lathe bed 21 also has a pair of support column 21E and the 21F that is arranged between upper and lower plate 21C and the 21D.The relative axle head of forming rolls 27 can be rotated to support on two support column 21E and the 21F by the bearing (not shown).

B. material clamping element 22 (Fig. 1 to 6)

Material clamping element 22 as illustrated in fig. 1 and 2 has left and right clamping

housing

31 and 32, and they are arranged on the radially opposite side of forming rolls 27 so that in the position that is symmetrical on forming rolls 27 roll axis a bit.As being fixed in left and

right clamping support

33 and 34 by construction bolt 28B at the left and right clamping housing 31 shown in Fig. 1,2 and 4 and 32.

Left and

right clamping support

33 and 34 as shown in Figure 5 and Figure 6 respectively has a groove 35, and upper and

lower clamping part

36A and 36B are arranged on wherein so that fix a rack material 11 between two clamping parts.Vertical moving in upper and lower clamping part 36A and the groove 35 of 36B in each clamping support 33 and 34.One split ring 37 is arranged between clamping part 36A and the 36B.

Paired clamping cam

38A and 38B are arranged on the outside of clamping part 36A and 36B.Clamping

support

33 and 34 respectively has and clamps oil pressure working chamber 41A and the 41B that plunger 39A that cam 38A is connected with the 38B spiral and 39B use.Oil pressure working chamber 41A and 41B respectively have first chamber 42 and second chamber 43 in each plunger 39A and the formation of 39B opposite side.Two

first chambeies

42,42 interconnect by a pipeline 44, and two

second chambeies

43,43 interconnect by a pipeline 45.

Therefore, for each, left and

right clamping support

33 and 34, the decline that

clamps cam

38A and 38B will cause that the oil pressure working fluid is fed to oil pressure working chamber 41A and 41B (Fig. 6 A), wherein, clamping

part

36A and 36B are closed together with stationary rack material 11.Therefore, one independently rack material is by a corresponding left and

right clamping support

33 or 34 fixing, and they are face-to-face in the radially opposite side of forming rolls 27 position in a symmetrical arrangement, gets ready for setting about the tooth bar processing that is shaped.Be shaped and add man-hour when finish tooth bar on each rack material 11, each left and

right clamping support

33 and 34 has the hydraulic fluid that is fed to corresponding

second chamber

43,43 from oil pressure working chamber 41A and 41B, makes to clamp

cam

38A and 38B (Fig. 6 A) rises.Like this, by the elastic force of spring 37 clamping part 36A is opened with 36B and to separate, thereby take out rack material 11 from each

clamping support

33,34.

Clamping

part

36A and 36B respectively have lower surface clamping part 46A, the 46B of a correspondence shown in Fig. 6 A and 6B.Each lower surface clamping part extends in each

corresponding clamping part

36A and 36B whole vertically and have one basically with the shape of tubulose rack material 11 complementations, so it can clamp whole the latter half of rack material 11 and the sub-fraction above its center line 11A.

C. plug adjusting device 23 (Fig. 2 and 4)

Each plug adjusting device 23A, 23B have plug oil cylinder or cylinder 62A, the 62B of a corresponding setting in left and

right clamping support

33 and 34 rear surfaces.Each plug oil cylinder or

cylinder

62A, 62B have respective link 26A, the 26B of stationary core

rod mounting bracket

63A, 63B on it.Above-mentioned each

plug

26A, 26B are installed on its corresponding

plug mounting bracket

63A, 63B.

Therefore, advance each

plug mounting bracket

63A and 63B by corresponding plug oil cylinder or

cylinder

62A, 62B, each

plug

26A, 26B are contained in the material insertion position between clamping part 36A and the 36B.Now, equipment 20 is prepared to begin tooth bar shaping processing with the plug 26A, the 26B that are inserted in accordingly in the rack material 11 on each rack material 11,11.When machining when being shaped at

corresponding rack material

11,11 upper racks, corresponding plug oil cylinder or

cylinder

62A, 62B withdraw from corresponding plug mounting bracket 63A, 63B.As a result, each

plug

26A, 26B leave

corresponding rack material

11,11.

In this embodiment, plug is loaded on the precalculated position of each processing.Yet, also the plug that is fixed on pre-stator position can be arranged.

D. material drive unit 24 (Fig. 1,2 and 4)

Material drive unit 24 has a base 70 that is fixed in lathe bed 21 upper plate 21C.The base 70 supporting reciprocating type oil cylinder of left and right tubular material or cylinder 71 and 72.The connecting rod of reciprocating type oil cylinder of tubular material or cylinder 71 on the left of left side clamping housing 31 is connected in by a left side connecting axle 71A, and right clamping housing 32 is connected in the connecting rod of the reciprocating type oil cylinder 72 of right side tubular material by a right connecting axle 72A.Left and right connecting

axle

71A and 72A have corresponding tooth bar 71B and 72B, and a pinion 73 is set between tooth bar 71B and 72B.Left and right connecting

axle

71A and 72A are driven during in the opposite direction with mutually synchronization mutually.Pinion 73 is bearing on the base 70.

Thereby, by decline or rising and synchronous by rising or the decline of right side tubular material reciprocating oil cylinder 72 manipulation right side connecting axle 72A by left side tubular material reciprocating oil cylinder 71 manipulation left side connecting axle 71A, the tubular material 11 that is fixed on left and right

side clamping housing

31 and 32 each

corresponding clamping support

33 and 34 in the opposite direction moves, simultaneously contact pressurized, make rack material mobile on its tangential direction on the forming rolls with the radially opposite flank of forming rolls 27.At this moment, forming rolls 27 rotates with counterclockwise or clockwise direction.Make left and right rack material 11 in above-mentioned rightabout rolling.Obviously, when left side connecting axle 71A rose, right side connecting axle 72A just descended, and counterclockwise rotated to cause forming rolls 27.

E. tooth depth adjuster (Fig. 1 and 2)

Tooth depth adjuster 25 has left and

right thread spindle

81 and 82, and they are rotatably supported on the left side plate 21A and 21B of lathe bed 21.

Thread spindle

81 and 82 is driven by motor 83 and 84.In addition, lathe bed 21 has on the left of the supporting slidably and a left-hand foot 85A and a right side base 86A of the horizontal sliding bottom 85 in right side and 86.Left side and the horizontal sliding bottom 85 in right side and 86 have nut 85B and the 86B that twists respectively on left and right sides thread spindle 81 and 82.The left side laterally clamps housings 31 in sliding bottom 85 supporting left sides, and one, promptly with respect to the tooth depth direction and can relatively move in the left side axial vertical direction of connecting axle 71A with respect to towards a left side with towards the direction on the right side.The horizontal sliding bottom in right side 86 supporting right sides clamp housings 32, and one, promptly with respect to the tooth depth direction and can relatively move in the right side axial vertical direction of connecting axle 72A with respect to towards a left side with towards the direction on the right side.By engaging of a groove and a protuberance, the horizontal sliding bottom 85 in left side and left side clamp housing 31, and the horizontal sliding bottom 86 in right side and right side clamp housing 32 and interconnect so that only move in an above-mentioned direction.

Tooth depth adjuster 25 makes

motor

83 and 84 period of motion work according to tubular material reciprocating oil cylinder 71 and 72, and motor is by causing the rotation of left and right

sides thread spindle

81 and 82 for a predetermined angular that is moved back and forth circulation by each of the left and right tooth strip material 11 that causes through material drive unit 24.Thereby left and right horizontal sliding

bottom

85 and 86 will be simultaneously towards a certain amount of scope of forming rolls 27 feedings.Left side and the horizontal sliding bottom 85 in right side make left and right clamping housing 31 vertically mobile synchronously with respect to 27 one-tenths of forming rolls with 32 with 86 feeding.Therefore, in the each motion cycle of left and right tooth strip material 11 with respect to forming rolls 27, the axle base between left and right rack material 11 each and the forming rolls 27 reduces, thereby, progressively strengthen the degree of depth that is formed on left and right rack material 11 rack tooths 12.

F. angle demodulator (Figure 4 and 5)

Angle demodulator 28 has the

clamping support

33 and 34 that is supported so that rotation on the left and right clamping

housing

31 and 32 of material clamping element 22.

Clamping support

33 and 34 is round, and cooperate in rotary steering hole 31A that in clamping

housing

31 and 32, is provided with and the 32A (Fig. 2), and each

clamping support

33 and 34 has a circular arc slotted hole 28A in groove 35 both sides of placing clamping

part

36A and 36B and clamping cam 38A and 38B.With construction bolt 28B rotation precalculated position in

rotary steering hole

31A and

32A clamping support

33 and 34 is fixed in clamping housing 31 and 32.Thereby each rack material 11 will be fixed in the material clamping element 22, as shown in Figure 8, and the angle that each rack material will be predetermined with respect to the axioversion one of forming rolls 27, so tooth bar 10 can have and axial at an angle the rack tooths 12 of rack material 11.

In tooth bar manufacturing equipment 20, the cross section profile of the plug 26 shown in Fig. 7 A have one with the rack tooth shaped portion of rack material 11 material support surface 90 at interval, this material support surface 90 is swelled.Material support surface 90 is suitable for being made of the

skewed surface

92,92 of a center plane surface 91 and opposite side.According to causing that by plug 26 the resistance to deformation resistance of boundary member inner surface between the plane surface forms the rack tooth 12 of rack material 11, and almost there is not periphery (because between the material support surface 90 of the boundary member inner surface of rack material 11 and plug 26 formation gap 101).Then, the plane surface of rack material 11 can smoothly entirely be out of shape by the thrust of forming rolls 27, and can not form to the phenomenon that presses down (Fig. 7 B) on the rack tooth shaped portion of rack material 11.Therefore, the degree of depth of rack tooth 12 becomes very even in facewidth direction.

The process of making tooth bar 20 with tooth bar manufacturing equipment 20 is described now.

With corresponding plug adjusting device 23A, 23B,

plug

26A, 26B are placed in the material insertion position between clamping part 36A and the 36B in each left and

right clamping support

33 and 34.

Left and right rack material 11 is placed on the clamping part 36A of each left and

right clamping support

33 and 34 and the material insertion position between the 36B.At this moment, plug 26 inserts the inside of rack material 11 again, and then, each rack material 11 is run into the brake that is arranged on each

clamping support

33 and 34 by its end face and caused at its fixed position longitudinal register.

Material clamping element 22 has been arranged, and left and right rack material 11 respectively is clamped between the clamping

part

36A and 36B of each left and right clamping support 33 and 34.Left and right tooth strip material 11 is fixed on the radially opposite side of forming rolls 27 face-to-face, make they with forming rolls 27 roll shaft axis on become on the point-symmetric position.

The horizontal sliding bottom 85 of the left and right side of tooth depth adjuster 25 and 86 is installed in a suitable supplying position with respect to forming rolls 27.Then, with material drive unit 24, make left and right side clamping support 33 vertical with 34 mobile.Thereby, the outer peripheral face of the material 11 wedging forming rolls 27 that in left and right

side clamping support

33 and 34, fix to clamp, this moment is by the inside of material support surface 90 supporting pipes of plug 26.In the method,, form hollow rack teeth 12 in each left and right rack material 11 on forming rolls 27 roll shaft axis by cold working when each left and right rack material 11 in the opposite direction a bit becomes point symmetry to close to tie up on the outer peripheral face of forming rolls 27 when mobile.

After this, in the each slip circulation of left and right side rack material 11 with respect to forming rolls 27, the horizontal sliding bottom 85 of left and right side and 86 passes through tooth depth adjuster 25 towards a certain amount of scope of forming rolls 27 feedings.Thereby the axle base between each left and right side rack material 11 and the forming rolls 27 dwindles, thereby, progressively increase the degree of depth of rack tooth 12, up to the rack tooth 12 that forms desired depth.

Aforesaid embodiment has following favourable effect.

According to the present invention, make rack material 11 and forming rolls 27 move mutually and can in rack material 11, form rack tooth 12 in the tangential direction of forming rolls 27 with material drive unit 24.At this moment, owing to forming rolls 27 presses to that rack material 11 causes that rack material 11 moves on forming rolls 27 and by the tangential direction of shaping roll 27, caused tangential force rotates into roll 27 to form rack tooth 12 when rack material 11 wedging forming rolls 27.

In other words, the step that forms a flat shaping of teeth surface on rack material 11 does not for the first time need, and on the contrary, can directly form rack tooth 12 in pipe.Simplify processing, thereby improved productivity ratio.

For forming rolls 27 and rack material 11 circulation of each predetermined quantities of motion mutually (for example circulation each time), reduce axle base between forming rolls 27 and the rack material 11 by tooth depth adjuster 25.Thereby forming rolls 27 increases progressively wedging material 11 for the circulation of each predetermined quantity of mutual motion, makes forming rolls 27 need not bigger power when each feed and only needs lower power just can form rack tooth 12.In addition, when forming rack tooth 12 with bigger power, formed rack tooth 12 does not have burr, and may form the rack tooth 12 with excellent mechanical strength.

Because material clamping element 22 comprises the angle demodulator 28 that changes 11 pairs of forming rolls 27 fixed angles of rack material, can be on rack material 11 axially meeting at right angles with rack material 11 forms rack tooth 12, or forms rack tooth 12 at an angle with rack material 11 axis directions.

Rack material 11 is arranged on radially opposite side of forming rolls 27 face-to-face, when they are in the opposite direction mobile, the thrust that is applied to forming rolls 27 by each rack material 11 owing to the symmetry of point with respect to a bit cancelling out each other on the forming rolls roll shaft axis.Therefore, needn't increase the bending stiffness of shaping roller diameter with assurance forming rolls 27, thus but the size of reduction equipment 20.

Even reduce the diameter of forming rolls, also be difficult to the roll shaft of bending forming roll 27, therefore, can increase forming pressure and can not sacrifice the machining accuracy of rack tooth.

Because the forming rolls diameter can reduce, the contact area between forming rolls 27 and the workpiece also reduces, to increase the thrust of unit are.Therefore, the rising of forming rolls 27 each motion cycle workpiece or feeding can be accelerated to reduce process time.Because two tooth bars form simultaneously, working ability is double.

Though describe embodiments of the invention in conjunction with the accompanying drawings in detail, special construction of the present invention never is limited to described embodiment, and can change without departing from the present invention and modification.For example, the tooth depth adjuster can reduce axle base between forming rolls and the rack material to the reciprocating every half cycles of rack material or every a plurality of circulation (promptly whenever predetermined rolling circulation).

In addition, the device of operation drives forming rolls with the forming rolls drive unit and also can not necessarily only based on material drive unit 24 mutually.

Though described preferred embodiment of the present invention in conjunction with the accompanying drawings in detail, they never limit the present invention.It should be understood that not breaking away under the scope of the invention that following claim states and the essence spirit situation and can make all changes and modification.

Claims

1. an equipment of making automobile steering rack is formed with rack tooth at tooth bar one side surface, comprising:

A rack material fixture that is used for fixing the hollow tubular rack material that is inserted with a plug in it, described fixture has a vertical axis;

The forming rolls that a vertical axis and an outer peripheral face are arranged, described forming rolls side face forms the rack tooth shape;

The mutual telecontrol equipment that rack material fixture and forming rolls are moved mutually, when described material and described roll when described steering rack shaping is in contact with one another, described fixture moves in the tangential direction in forming rolls orientation; And

A feed arrangement of adjusting distance between rack material fixture axis and the forming rolls axis,

The one processing area supported that separates by the space with the rack tooth shaped portion of rack material is arranged on the cross-sectional profiles of described plug, and this processing area supported is middle convex.

2. tooth bar manufacturing equipment according to claim 1 is characterized in that, the middle convex of processing area supported is made of the skewed surface of center plane surface and these plane surface both sides, center.

3. tooth bar manufacturing equipment according to claim 1 is characterized in that the rack material fixture comprises that one is used for changing the angle regulator of rack material to the forming rolls fixed angles.

4. tooth bar manufacturing equipment as claimed in claim 1, it is characterized in that, the rack material fixture can be fixed two rack material, and face-to-face at forming rolls opposite side radially, the device of motion makes each rack material move in mutually opposite direction to each described tooth bar mutually mutually.

5. tooth bar manufacturing equipment as claimed in claim 3, it is characterized in that, the rack material fixture can be fixed two rack material, and each described tooth bar is forming radially opposite side of roll mutually face-to-face, and the device of motion makes each rack material move in mutually opposite direction mutually.